About the Brain & Behavior AG

Our main goal is to understand the neural networks that give rise to natural behaviors, with a strong focus on the circuits that enable vocalization and hearing in mammals.
Our work combines electrophysiology, computational modelling, brain perturbation techniques, and behavioral measurements. 
Our research is conducted in non-human model organisms (mostly bats but also rodents) as well as in humans, and in brain organoids. 
Note that the lab is currently distributed between Berlin (FU) and Frankfurt (ESI).

We pursue three main research lines:

(I) 

Brain insights from in-vitro experiments (cerebral organoids). Cerebral organoids derived from human pluripotent stem-cells offer many advantages for basic and clinical research 
when behavioral assessments are not required. While organoids are potentially very useful, we still know very little about how much these man-made structures resemble an actual brain 
in terms of the functional properties of individual neurons and neural assemblies. The B&B lab bridges this gap by studying organoids using electrophysiology and pharmacological manipulations, 
similar to those classically used to study the natural brain (Fig. 1). This work is conducted in a branch of the group located at Ernst Strüngmann Institute (ESI) 
in Frankfurt while the labs at the FU Berlin are in preparation.

Figure1: recording of action potentials in a cerebral organoid.

(II)

The brain in-vivo (studies during vocalization and hearing). What happens in the natural brain when we listen to external sounds or when we speak? These are tasks that are not 
unique to humans, but that many animals have to solve on a daily basis, using neural circuits that have been adapted and largely preserved over millions of years of evolution 
(see example bat vocalizations in figure 2).

Figure 2: Examples of the bat’s “voice”. Bats used highly stereotyped high-pitched sounds to navigate the environment (echolocation) and low-pitched sounds for social communication.

In the B&B Lab, we use a comparative approach to study how sounds are perceived and produced across species, and what makes them ethologically relevant to the animal. 
Our comparative work focusses on bats and humans as model organisms at the intersection of neural oscillations (see example signals in Fig. 4), spiking activity and naturalistic behavior. 
Understanding how mammals (humans and non-humans) hear and vocalize is important for both clinical and conservation purposes.

Figure 3: Distinct oscillations in two heavily interconnected neocortical areas of bats.

Beyond vocal production and hearing, our research also investigates how the brain gives rise to perception, thought, and awareness. Using a neuroethological approach, 
we aim to study these processes in the context of natural behavior in humans and across species. Through brain recordings and brain stimulation techniques, 
we examine how rhythmic patterns of neural activity shape the way we experience the world and how these dynamics vary across individuals 
(see example electrode placement to study the human brain non-invasively).

Figure 4: Non-invasive neural measurements and electric stimulation to study the human brain.

(III)

The brain in silico. In silico experiments conducted via computer simulations (see example in Fig. 6) are a tool used by my group to make sense of complex data 
obtained in-vivo and in vitro (see above). Computational modelling is a fundamental part of our work, and we use it to derive the neural networks that give rise to behavior 
and natural neural representations and to optimize and plan brain stimulation protocols. Our in-silico work produces precise guiding hypotheses that ultimately reduce 
the number of experiments required to understand the brain and behavior.

Figure 5: An integrate-and-fire neuron model explains the context -dependent responses to of auditory cortex neurons.

Together, our work in organoids, non-human animal models, humans, and computer simulations helps us build a unified understanding of how brain networks generate behavior 
and experience across levels of organization and species.